I am not in QF (judging by your id I think I might be in the same company as you)
AB3 and idle reverse will give you more or less the same stopping dist. as AB3 and full reverse.
Operating into busy airfields and dawdling down the RWY using AB2 is not likely to get favourable commentary from the tower.
Must admit full rev is probably a bit of overkill if the rwy is long and dry, but I am sure they thought it through before they implemented it.
With my lot AB3 and idle rev. is the "standard" landing set up.